Membrane fabrics

The following list is a summary of the more popular materials listed in order of popularity.

Permeable Shadecloth

Shadecloth is a knitted HDPE fabric which is clearly the most popular fabric used for tension membranes due to it’s high strength/weight ratio, low cost and modest support structure requirement.

We find the following to be the most popular in this category.

Extrablock – High minimum tensile strength, good shade & UV protection (over 90%), some colours are Fire retardant, low stretch.  This type of fabric has an economic* life of up to 12 years, although we recommend the membrane be resewn after 6 years. The following link contains information about colours and technical specification. A summary of the warranty provided by Halifax Vogel is that it covers  against UV degradation on a pro rata diminishing value basis for 10 years and covers fabric only( Does not include manufacturing or installation). Refer to Halifax Vogel for full terms of warranty. For colour swatches and technical information go to our downloads page.

Synthesis AF 350 – High minimum tensile strength, good shade & UV protection (over 90%), low and relatively even stretch along waft and weft. See the link for the specifications. This type of fabric has an economic* life of up to 12 years, although we recommend the membrane be resewn after 6 years. The following link contains information about colours and technical specification. A summary of the warranty provided by Gale Pacific is that it covers against UV degradation on a pro rata diminishing value basis for 10 years and covers fabric only( Does not include manufacturing or installation). Refer to Gale Pacific for full terms of warranty. For colour swatches and technical information go to our downloads page.

Permeable PVC Mesh

Permeable PVC mesh is normally used in rollup blind and awning applications. It has a higher tensile strength and less stretch than permeable shadecloth, shading is typically around 90% how ever it can vary widely, industrial PVC mesh applications where shading is reduced to 60% but a higher tensile strength is required. Approximately 2 to 4 times the tensile strength of shade. The open weave of PVC mesh means it effectiveness for solar protection is severely diminished and is considerably more expensive than shadecloth. There are too many different type of materials to comment on thsi website. However the following links will take you to websites for market leaders. Mermet, Mehler, Hiraoka

Waterproof PVC

PVC fabric consists of  polyester scrim which is coated with a UV stabilised PVC. The coatings usually include other materials such as fire retardant and PVDF (which assists in keeping the membrane clean). Within this class there are many different suppliers of fabric and they often make fabrics for very special purposes. As we are primarily a tension membrane manufacturer our comments are confined to the materials which will be of use to our customers.

Tension Membrane (TM) Grade PVC

The scrim layer of TM PVC is a densely woven layer of low stretch, low wick yarns. This is coated with PVC on both sides. The PVC includes a mixture to fire retardant to reduce the risk of fire spreading and UV stabilisers. TM PVC has a high level of UV stabilisers because it is expected to have an economic* life of up to 25 years.  TM PVC is usually white or pearl white to minimise fading. Some manufacturers also make metallic coated fabric in silver and gold. This type of fabric is suitable for large scale projects. For colour swatches and technical information go to our downloads page.

Architectural Grade PVC

The scrim layer of Architectural Grade PVC is a densely woven layer of low stretch, low wick yarns. This is coated with PVC on both sides. The PVC includes a mixture to fire retardant to reduce the risk of fire spreading and UV stabilisers. Architectural grade PVC has a high level of UV stabilisers because it is expected to have an economic life of up to 15 years*.  Architectural grade PVC has a typical weight of between 600 and 700 grams per square metre (GSM) and a tensile strength of up to 3kN/50mm. This type of fabric is suitable for small tension membranes (Under 70 m2), awnings tents etc.  Colour fastness is good but there will be some fading. Technical information and colours swatches for two of the better fabrics is in our downloads page.

Commodity Grade PVC

As the name implies, this type of material is manufactured down to a price and not up to a standard. The quality of the materials and the elements vary considerably. They are normally used by the transport and bulk materials handling as tarpaulins where they use then for 2 to 3 years and dispose of them. They can be used for micro (under 20m2) tension membranes . Typical economic life is 5 – 6 years

Waterproof LDPE

Consisting of dense polyethylene or polyolefin they do not have a scrim layer and are only suitable for low tension applications. However with increasing community pressure to use materials with low VOC emissions, through further research these may become the Tension Membranes materials of the future (with some further research). A supplier with the largest range of LDPE fabrics is Hagihara, link attached Hagihara (warning this site is in Japanese)

Waterproof PTFE coated glass

Undoubtedly the premier tension membrane grade material (with a price to match), this type of material is suitable for large scale projects which require an long (40+ years) economic life. They are non combustible and highly resistant to most soiling. The raw material is 4 times the price of TM Grade PVC, the fabric is usually made to order and hence there is usually a time delay of 8 weeks between order and delivery, they are difficult to manufacture, transport and install. Hence the substantially higher cost.

Other materials

The following other materials are worth mentioning but as collectively they account for less than 0.1% of the market we will not go into any detail.  Sinlicone coated fibreglass, PVC coated aramid, PVDF coated PTFE, ETFE foils.

* Economic life is an estimate based on previous experience. Factors known to shorten the economic life include exposure to chlorine, bleach or other harsh chemicals. Depletion of the ozone layer is an increasing problem that is worse in some areas. Hence the stated period is not assured.

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